Plant desiccation tolerance is an important factor that relates to the labor reduction in cultivation of various crops and garden plants and to the expansion of cultivable areas. If improvement of desiccation tolerance by genetic engineering can overcome the difficulties in crop cultivation in arid regions, the possibility of it as a countermeasure against world food shortage can be expected. Previous reports of experimental examples in which desiccation tolerance was improved by genetic recombination include enhanced trehalose synthesis (Non-Patent Document 2: Garg et al., (2002) Proc. Natl. Acad. Sci. USA 99, 15898-15903) and introduction of the peroxidase gene (Non-Patent Document 6: Llorente et al., (2002) Plant J. 32, 13-24). Moreover, an example of increasing desiccation tolerance with the use of transcription factor genes is introduction of the DREB gene comprising an AP2 domain (Non-Patent Document 4: Kasuga et al., (1999) Nat Biotechnol 17, 287-291).
ZPT2-3 (renamed from EPF2-7) is a zinc finger transcription factor of Petunia hybrida (petunia). The present inventors previously isolated the ZPT2-3 gene from petunia and found that it was specifically expressed in floral organs; however, its function remained unclear (Non-Patent Document 7: Takatsuji et al., (1994) Plant Cell 6, 947-958). Recently, it was found that wounding, low temperature, and treatment with heavy metals induce the expression of ZPT2-3 gene and that a jasmonic acid-mediated signaling pathway is involved in the induction of the expression. At the same time, it was also found that in adult leaves, the expression of the gene was not induced in response to desiccation treatment or high salt concentration (Non-Patent Document 9: The Japanese Society of Plant Physiologists, Annual Meeting in 2001 Abstracts; Non-Patent Document 10: 25th Annual Meeting of the Molecular Biology Society of Japan). Soybean SCOF-1 that confers freezing tolerance (Non-Patent Document 5: Kim et al., (2001) Plant J. 25, 247-259), Arabidopsis thaliana RHL41 that confers tolerance to high-intensity light (Non-Patent Document 3: Iida et al., (2000) Plant J. 24, 191-203), and Medicago sativa Mszpt2-1 involved in nodulation (Non-Patent Document 1: Frugier et al., (2000) organogenesis. Genes Dev. 14, 475-482) are known as structurally similar zinc finger genes. However, zinc finger genes that confer desiccation tolerance when introduced into plants are still unknown.    Non-Patent Document 1: Frugier et al., (2000) organogenesis. Genes Dev. 14, 475-482.    Non-Patent Document 2: Garg et al., (2002) Proc. Natl. Acad. Sci. USA 99, 15898-15903.    Non-Patent Document 3: Iida et al., (2000) Plant J. 24, 191-203.    Non-Patent Document 4: Kasuga et al., (1999) Nat Biotechnol 17, 287-291.    Non-Patent Document 5: Kim et al., (2001) Plant J. 25, 247-259.    Non-Patent Document 6: Llorente et al., (2002) Plant J. 32, 13-24.    Non-Patent Document 7: Takatsuji et al., (1994) Plant Cell 6, 947-958.    Non-Patent Document 8: Takatsuji et al., (1992) EMBO J. 11, 241-249.    Non-Patent Document 9: The Japanese Society of Plant Physiologists, Annual Meeting in 2001 and the 41st Symposium, Abstracts p. 174    Non-Patent Document 10: 25th Annual Meeting of the Molecular Biology Society of Japan, Program and Abstracts p. 809